Contact Resistance of Microbumps in a Typical Through-Silicon-Via Structure

The contact resistance of microbumps in a plastic ball grid array packaging with a through-silicon-via (TSV) structure was characterized. Accordingly, a self-designed TSV daisy-chain circuit was proposed to facilitate the formulation of the measurement paths, and the test samples were made by using a commercialized packaging process to simulate real product behaviors. Using the proposed single model and the complete model for the testing structure, about 25 $\text{m}\Omega $ was measured as the average contact resistance per microbump, and the contact resistance for each microbump was separately extracted between 4 and 60 $\text{m}\Omega $ In addition, decreasing contact resistance due to the annealing effect was observed from two different reliability tests.